A prospective, randomized comparison of the LMA-protector™ and i-gel™ in paralyzed, anesthetized patients

BackgroundIn the present study, we compare the LMA-Protector (TM) and the i-gel (TM) in terms of adequacy of the airway seal, insertion time, ease and accuracy of insertion, and the incidence of postoperative sore throat.MethodsIn 110 anesthetized and paralyzed adult patients, the i-gel (TM) (n=55) or the LMA-Protector (TM) (n=55) was inserted. The primary outcome was airway leak pressure. The secondary outcomes included the first-attempt success rate, insertion time, ease and accuracy of the device insertion, ease of gastric tube placement, blood staining on the device after removal, and incidence and severity of postoperative sore throat.ResultsThe airway leak pressure was higher with the LMA-Protector (TM) than with the i-gel (TM) (31 [7] cmH(2)O vs. 27 [6] cmH(2)O, respectively; P=0.016). Insertion time was longer with the LMA-Protector (TM) than with the i-gel (TM) (27 [16] sec vs. 19 [16] sec, respectively, P<0.001), but ease of insertion and the first-attempt success rate were not different between the two groups. The LMA-Protector (TM) provided a worse fiberoptic view of the vocal cords and more difficult gastric tube insertion than the i-gel (TM) (both P<0.001). Blood staining on the device was more frequent with the LMA-Protector (TM) than with the i-gel (TM) (P=0.033). The incidence and severity of postoperative sore throat were not different between the two groups.ConclusionThe LMA-Protector (TM) provided a better airway sealing effect than the i-gel (TM). However, it required a longer insertion time, provided a worse fiberoptic view of the vocal cords, and caused more mucosal injury compared to the i-gel (TM).Trial registrationClinicalTrials.gov (NCT03078517). Registered prior to patient enrollment, Date of registration: Mar 13, 2017.